1. Field of the Invention
This invention relates to an initially closed openable and reclosable closure for a flexible bag. Flexible bags having a closure of this invention may be initially filled through an unsealed edge region between a front and rear film, sealed in the area of the filling to provide an initially closed bag containing desired contents which later can be opened at a different region for removal of the contents followed by insertion of the same or different contents and then reclosed at the later opening, preferably resealed in a tamper evident manner only with the use of the hands and without the need for any tools or appliances. Reclosable flexible bags of this type are especially useful for providing medical test materials which may be removed from a closed bag by the user, used as desired and returned to the same bag and reclosed in a tamper evident manner for return to a medical laboratory for analysis.
2. Description of Related Art
Various types of closures and seals for flexible bags have been known over the years of use of such bags. A multitude of efforts have been made to provide reclosable and/or resealable flexible bags for a wide variety of specialized uses. In recent years tamper evident seals have become important, particularly in food and health care environments.
Exemplary of adhesive sealing of open tops of containers after filling with desired contents are: U.S. Pat. No. 4,759,643 teaches a self-sealing, non-resealable envelope wherein an adhesive area at the top portion of a longer flap seals to both sides of the upper portion of a shorter flap when the longer flap is folded over the top of the shorter flap; U.S. Pat. No. 4,785,940 teaches a pressure sensitive adhesive closure strip on the front surface of a back panel of a flexible bag which when folded over a shorter front panel adheres to the front surface of the shorter front panel; and U.S. Pat. No. 4,510,621 teaches an adhesive to adhesive sealing material on the exterior surface of one plastic film web on opposite sides of a transversly extending access opening slit in that web of a pouch, the opening being sealed by folding the pouch over upon itself along the opening slit after placement of contents into the pouch so as to bring the adhesive into confronting relation with itself to form the adhesive-to-adhesive seal.
Likewise, a number of efforts have been made to provide reclosable flexible bags which also provide tamper evident initial opening seals: U.S. Pat. Nos. 4,786,190 and 4,925,316 teach a reclosable peal seal and a reclosable zipper seal, respectively, exterior to a non-reclosable tamper evident seal; U.S. Pat. No. 4,759,642 teaches a zipper-type reclosable seal exterior to a peal seal in a bag with corner chamfers; U.S. Pat. No. 2,991,001 teaches a resealable container with a permanent seal exterior to a pressure sensitive resealable seal, necessitating removal of a tear strip to expose the pressure sensitive adhesive; U.S. Pat. No. 4,927,271 teaches a zipper-type reclosable means having a sealed tamper evident hood enveloping the opening area, opening being first achieved by removal of the top portion of the hood; and U.S. Pat. No. 4,832,505 teaches a zipper-type reclosable means having the sides of a bag extending above the reclosable means and sealed, necessitating removal of the extending sides to obtain first access to the interior and the reclosable means.